One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,3,4)(7,11)(10,12)(14,20)(15,22)(17,18)(21,28)(23,24)(25,26)(2,4)(5,6)(7,10)(8,9)(11,12)(13,14)(15,21)(16,22)(17,24)(18,20)(19,23)(25,27)(26,28) involution — undirected(6,9)(10,12)(13,15,19,26)(14,21,23,28)(16,20,27,24)(17,22,18,25)(5,7,8,11)(6,10,9,12)(13,16)(14,22)(15,20)(17,28)(18,21)(19,27)(23,25)(24,26)(14,23)(16,27)(20,24)(21,28) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.